// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (c) 2020 FUJITSU LIMITED. All rights reserved.
 * Author: Yang Xu <xuyang2018.jy@cn.jujitsu.com>
 *
 * This is a basic ioctl test about loopdevice.
 *
 * It is designed to test LO_FLAGS_READ_ONLY (similar as losetup -r)
 * and LOOP_CHANGE_FD.
 *
 * For LOOP_CHANGE_FD, this operation is possible only if the loop device
 * is read-only and the new backing store is the same size and type as the
 * old backing store.
 */

#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>
#include "lapi/loop.h"
#include "tst_test.h"

static int file_fd, file_change_fd, file_fd_invalid;
static char backing_path[1024], backing_file_path[1024], backing_file_change_path[1024];
static int attach_flag, dev_fd, file_fd;
static char loop_ro_path[1024], dev_path[1024];

static void verify_ioctl_loop(void)
{
	struct loop_info loopinfoget;

	dev_fd = SAFE_OPEN(dev_path, O_RDWR);
	SAFE_IOCTL(dev_fd, LOOP_SET_FD, file_fd);
	attach_flag = 1;

	TST_ASSERT_INT(loop_ro_path, 1);
	TST_ASSERT_STR(backing_path, backing_file_path);

	memset(&loopinfoget, 0, sizeof(loopinfoget));

	/*
	 * In drivers/block/loop.c code, set status function doesn't handle
	 * LO_FLAGS_READ_ONLY flag and ignore it. Only loop_set_fd with readonly
	 * mode, lo_flags will include LO_FLAGS_READ_ONLY.
	 */
	SAFE_IOCTL(dev_fd, LOOP_GET_STATUS, &loopinfoget);

	if (loopinfoget.lo_flags & ~LO_FLAGS_READ_ONLY)
		tst_res(TFAIL, "lo_flags has unexpected %d flag", loopinfoget.lo_flags);
	else
		tst_res(TPASS, "lo_flags only has default LO_FLAGS_READ_ONLY flag");

	TEST(write(dev_fd, "xx", 2));
	if (TST_RET != -1)
		tst_res(TFAIL, "write succeed unexpectedly");
	else
		tst_res(TPASS | TTERRNO, "Can not write data in RO mode");

	TEST(ioctl(dev_fd, LOOP_CHANGE_FD, file_change_fd));
	if (TST_RET) {
		tst_res(TFAIL | TTERRNO, "LOOP_CHANGE_FD failed");
	} else {
		tst_res(TPASS, "LOOP_CHANGE_FD succeeded");
		TST_ASSERT_INT(loop_ro_path, 1);
		TST_ASSERT_STR(backing_path, backing_file_change_path);
	}

	TEST(ioctl(dev_fd, LOOP_CHANGE_FD, file_fd_invalid));
	if (TST_RET) {
		if (TST_ERR == EINVAL)
			tst_res(TPASS | TTERRNO, "LOOP_CHANGE_FD failed as expected");
		else
			tst_res(TFAIL | TTERRNO, "LOOP_CHANGE_FD failed expected EINVAL got");
	} else {
		tst_res(TFAIL, "LOOP_CHANGE_FD succeeded");
	}

	SAFE_CLOSE(dev_fd);
	tst_detach_device(dev_path);
	attach_flag = 0;
}

static void setup(void)
{
	int dev_num;

	char *tmpdir = tst_get_tmpdir();
	dev_num = tst_find_free_loopdev(dev_path, sizeof(dev_path));
	if (dev_num < 0)
		tst_brk(TBROK, "Failed to find free loop device");

	tst_fill_file("test.img", 0, 1024, 10);
	tst_fill_file("test1.img", 0, 1024, 10);
	tst_fill_file("test2.img", 0, 2048, 20);

	sprintf(backing_path, "/sys/block/loop%d/loop/backing_file", dev_num);
	sprintf(backing_file_path, "%s/test.img", tmpdir);
	sprintf(backing_file_change_path, "%s/test1.img", tmpdir);
	sprintf(loop_ro_path, "/sys/block/loop%d/ro", dev_num);

	free(tmpdir);

	file_fd = SAFE_OPEN("test.img", O_RDONLY);
	file_change_fd = SAFE_OPEN("test1.img", O_RDWR);
	file_fd_invalid = SAFE_OPEN("test2.img", O_RDWR);
}

static void cleanup(void)
{
	if (dev_fd > 0)
		SAFE_CLOSE(dev_fd);
	if (file_fd > 0)
		SAFE_CLOSE(file_fd);
	if (file_change_fd > 0)
		SAFE_CLOSE(file_change_fd);
	if (file_fd_invalid > 0)
		SAFE_CLOSE(file_fd_invalid);
	if (attach_flag)
		tst_detach_device(dev_path);
}

static struct tst_test test = {
	.setup = setup,
	.cleanup = cleanup,
	.test_all = verify_ioctl_loop,
	.needs_root = 1,
	.needs_tmpdir = 1,
	.needs_drivers = (const char *const []) {
		"loop",
		NULL
	}
};
